The goal of the CHIL project was to make everybody’s daily life easier. CHIL was an integrated European research project with 15 project partners in Europe and in the US aiming to bring friendlier and more helpful computing services to society. Rather than requiring user attention to operate machines, CHIL services attempt to understand human activities and interaction in order to provide helpful services implicitly and unobtrusively. In CHIL, socially supportive environments proactively support human gatherings. Such environments offer, for example, meeting assistants that track and summarize human interactions in lectures, meetings, and office interactions.

The CHIL Ontology was developed to provide a formal high level description of the CHIL domain of discourse that can be efficiently used to build intelligent applications. As such, the CHIL ontology introduces a common programming language agnostic object model that can be used to formally represent elements of the CHIL domain of discourse. By using the Description Logics based Web Ontology Language (OWL DL) to model concepts, roles, and individuals of the CHIL domain of discourse it is possible to use a reasoner in order to automatically make implicit knowledge explicit, which can actually be considered as a form of artificial intelligence.

CHIL was co-funded by the European Union through the Information Society Technologies (IST) priority in the Sixth Framework Program.

The CHIL Knowledge Base Server

is an adapter for existing ontology management systems.

The Web Ontology Language (OWL) is the W3C standard that can be used to formalize all kinds of knowledge. However, there are no widely accepted standards yet that define APIs to manage ontological data. Processing ontological information still suffers from the heterogeneity imposed by the plethora of available ontology management systems. Moreover, ubiquitous computing environments usually comprise software components written in a variety of different programming languages, which makes it particularly difficult to establish a common ontology management API with programming language agnostic semantics.

The CHIL Knowledge Base Server exposes the functionality of arbitrary off-the-shelf ontology management systems via a formally specified and well defined API. Based on Floyd-Hoare logic and Description Logics terminology, a formal specification of the CHIL Knowledge Base Server API was devised in order to make it possible to consistently adapt off-the-shelf ontology management systems and to provide knowledge base clients with well defined operational OWL API semantics.

In the current release, the CHIL Knowledge Base Server adapts the Jena Semantic Web Framework with integrated JDBC connectivity for MS SQL, MySQL, and PostgreSQL database management systems.

Client libraries for the XML-over-TCP interface of the CHIL Knowledge Base Server are available for Java, C#, and C++. The CHIL Knowledge Base Server is available as a standalone Java application and as an Eclipse plug-in, which makes it particularly easy to develop both a software application and the underlying ontology in the same workbench in an integrated and convenient way.

Source Code

The source code of the CHIL Knowledge Base Server is available on


The CHIL Knowledge Base Server is available under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE Version 3 license.


2009 Computers in the Human Interaction Loop, Human-Computer Interaction Series, Springer Verlag ch. Ontological Modeling and Reasoning BibTeX
2009 Applied Intelligence Journal A Formally Specified Ontology Management API as a Registry for Ubiquitous Computing Systems BibTeX
2006 3rd IFIP Conference on Artificial Intelligence Applications & Innovations (AIAI) A Formally Specified Ontology Management API as a Registry for Ubiquitous Computing Systems BibTeX
2005 2nd International Conference on Embedded Software and Systems (ICESS) An Ontology-based Framework for Dynamic Resource Management in Ubiquitous Computing Environments BibTeX
2005 1st Australasian Ontology Workshop (AOW) A Pluggable Architectural Model and a Formally Specified Programming Language Independent API for an Ontological Knowledge Base Server BibTeX